Internal-combustion engine



April 24, 1928.

, M. MARTIN ET AL.

INTERNAL coMBUsTIoN ENGINE Filed Dec. 1s. .1927

3 Sheets-Sheet 1 y H y. Y

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M. MARTIN ET AL INTERNAL coMBUsTI'oN ENGINE Filed Dec. 16. 1927 5Sheets-Sheet 2 April 24, 1928. v

' M. MARTIN ET Al.

INTERNAL COMBUSTION ENGINE Filed Deo. 1a 1927 s sheets-sheetl 5 PatentedApr. 24, 1928.

UNITED STATES.

1,666,941 PATENT OFFICE.

MORRIS 'MARTIN, 0F CURL CURL, NEAR' SYDNEY, AND WILLIAM ROBERT yWERNER,

OF NYMAGEE, NEW SOUTH f1-MILES, AUSTRALIA.

INTERNAL-COMBUSTION ENGINE.

Application inea December 16, 1.927, serial No. 240,542,A arid in.YAustralia `october 15, 1926.

This invention relates toanint'ernal combustion engine of thereciprocating type and particularly to an improved construction whereintwo combustion or firing chambers are arranged in tandem fashion and twoseparate pistons, one for each of said chambers, are coupled together soas to drive the crankshaft ofthe engine through a common connecting rod.

Our invention also features -improved means of lubricating the engineparts. In the accompanying exemplary drawings Figure 1 y is a sectionalvview .ofthe improved enlgine showing the positions ofthe pistons duringtheexplo'sion inthe lower of i the tandem cylinders.

Figure 2 is a sectional viewfshowing the positions of thepistons duringthe explo-V sion in the upper cylinder.

Figure 3 is a detail view'in section show-l i ing the generalarrangement ofthe ylubricating system for the working parts of theengine.

Figure 4 is'a detail view of the lubricating oil pump.

As illustrated in these views, the improved engine comprises twolcombustion or tiring cylindersp2 and 3 arranged in tandem fashion yandpreferably vertically. `Each ofv these cylinders is-provided with anencircling cooling jacket l1 for the circulation of water Vor suitablecooling fluid, and a further cooling jacket 5 is preferably interposedbetween the cylinders to effectively cool the tiring ends ofthe;rcylinders.

Slidably ittedwithin the cylinders are pistons 6 and 7 respectively,Vrigidly coupled together by a piston rod 8 which is slidable in a glandor packing 'member 9 .Vitted through thecooling. jacket 5. The lowerpiston 7 is connected by a gudgeon pin 10 to aconnecting rod 11 throughwhich the power strokes of both pistons yare transmittedto drive theengine crankshaft A12.

The crankcase 18 lof the engine is connected to the lower open end ofthe cylinder 3 and is used'as an induction and compres-V sion chamberforyforcing gaseous fuel mixture into the firing end of said lower cylinder3 through a transfer passage 14. The crankcase is connected yto acarbureter 15 by a fuel induction pipe 16 provided near to its.

lower end with a non-return valve 17 to lprevent backow ofthe gaseousyfuel .during thecompression of the fuel withinthe crankcurved shape isconnected to the .upper end of the cylinder 2 andis adapted to deliverthe compressed 'gaseous fuel tothe-lower liring. end of said cylinderthrough a transfer passage 20%'` formed in the cylinder Cfflsln-iV s fThecylinders are provided with exhaust ports 21 and 22', and spark plugs23and 24, while .the-pistonsG and 7 preferably have: deflecting rvane s25`an d 26 arranged Vadjacent to the transfer ports to detlect'the'incoming gaseous'fuel mixture towards the ends ofthe cylinders in theordinary Vmanner to satisfactorily expel the burnt gases.`

; lntheoperation of the engine, chargesof gaseous fuel mixture areexploded alternately inthe upper and lower cylinders 2 and, andthevpower strokes of both pistonsr l a vfuel charge'- is compressed inthe firing thevlower piston 7 gaseousfuel mixture is i compressed 1n thecrankcase -13,.wh1le" 1n the downward movement of the upper piston (VYendof the cylinder 2 and fuel mixture-is also induced into kthe upperend of the cylinder 2 through the induction'pipe` 18 and valve 19.

Towards the termination of the. powervstroker of the lower vpiston 7 theexhaust port 22 isuncovered by the piston toV allowl the burnt gases toescape to atmosphere,k and los y z,

later the end of the transfer passage 14V is uncovered to admit thecompressed fuel mix= ture from the enginecrankcase 13 into the vfiringendy of the cylinderBi. The incoming I gases are deflected upwardlywithin the cylinder by the vane 26, thus causing the burnt gases to bedisplaced and satisfactorily expelled.

The compressed charge of fuel mixture in the upper cylinder 2 is nowfired by the spark plug 23 (see Figure 2), causing both of the pistonsto be forced upwardly within their cylinders. The upward movement of thepiston 6 compresses the quantity of fuel mixture in the upper end of thecylinder, while the upward'movement ofthe lower piston 7 *compresses thefresh fuel charge lin the upper end of the cylinder 3 and also inducesyfuel n'iixture` into, the crankcase 13 through the induction pipelG andvalve 17,. At the termination of the explosion stroke vof the pistone,the exhaust port 21` and transfer passage 20a are uncovered andcompressed fuel mixture from lthe upper end of the cylinder 2 isadmitted tothe firing end of said cylinder through the pipe y20 and saidtransfer passage 20a' to expel 'theburnt gases.

The fuel mixture in th'elower cylinder is then Yfired by the spark plug24 and the sequence of operations herein described is repeated, thecylinders firing alternately and two impulses being imparted through theconnecting rod 11 to the crankshaft l2 in each complete revolution.

By the invention increased driving power is obtained without appreciablyincreasing the dimensions of the engine, and, further'- more,"an eventorque upon the crankshaft is obtained, both of'which advantages arehighly desirable.

The lubricating system for the engine comprises an oil sump* 27 providedinthe lower end of the crankcase v13 anda gear pump 28 mounted in acasing 29y within the crankcase. The pumpv 28 consists of a large gearwheel 3() ymounted directly on the engine crankshaft 12 and a small gearwheel 31 meshing` with saidwheel 30 and loosely mounted on a pin orspindle The lubricating oil in the sump 27 is elevated by the pumpthrough apipe 33 and straining screen 34 and forced through a diagonalpassage 35 to the crankshaft bearing 3G. From the bearing 36 the oilpasses through a duct 37 to an axial passageway 38 formed in thecrankshaft and is forced to the crank pin bearing 39 and then upwardlythrough a hole 40 in the piston road 1l to the gudgeon pin bearing-ofthe lower piston 7 p and the walls of the cylinder 3.

The lubricating oil from the pump is also forced upwardly through a pipe,41 lto a passageway 42 formed in the cooling jacket '5, and is'delivered via the passa-ge 43 to the gland or packing member k9for thelubrication of thesliding'piston rodxS; A pipe 44 conducts lubricatingoil'from the passageway 42 and delivers it through a tube 45. into thetubular upper end 46l of the piston rod 8. During the lreciprocatingmovement of the upper piston 6, lthel tube sldably moves within thetubular 'end` 46 of said rod 8 and the oil is forcedoutvvardly i throughports or passages 47 inthey piston to lubricate the walls of the upperclyinder 2` lhat we do claim is:,- 7

An improved internal combustion yengine comprising, two combustionor'fii-'ing cylinders arranged in tandem fashion, two pistons slidableone in each ofsaid cylinders, a rod rigidly Vcouplingl said pistonstogether for movement in unison, an engine crank# shaft, a singleconnecting roctadaptedfto transmit the power strokes of both "pistons tosaid crankshaft, a crankcase wherein gaseous fuel mixture is compressed,a ltransfer passage delivering saidA compressed fuel mixu ture from thecrankcase vto one of the engine cylinders, means for supplying "gaseousfuel mixture to one end of the other cylinder forl compression, atransfer pipe delivering said compressed fuel mixturey from saidsupplyfing means tothe firing end of'said 'other cylinder, and means for firingthe fuel charges alternately in said cylinders.

In testimony whereof we` afiix ounsignatures.

Mouais MARTIN. l 'WILLrAM ROBERT WERNER.

